Filter and pump for a recirculating sanitary system

ABSTRACT

In a recirculating sanitary system, an improved filter and pump assembly provides a source of flushing liquid. A diaphragm pump is provided with a coupling to a plurality of needle members that reciprocate through an apertured plate. The needle members extend beyond the plate into the storage tank at all times, and the reciprocating motion imparted to the needle members tends to clean the needle-aperture combination, which acts as the filter. The pump also supplies a limited back flow through the filter for cleaning purposes during a portion of the operating cycle.

United States Patent 1191 1111 3,708,806

Kemper 1 Jan. 2, 1973 [54] FILTER AND PUMP FOR A [56] References CitedRECIRCULATING SANITARY SYSTEM I UNITED STATES PATENTS [75] Inventor:James M. Kemper, Hollywood,

C If 1,877,449 9/1932 Fulcher ..21o/413x 2,321,786 6/1943 Wotton...210/413x 73 A M 2,994,434 8/1961 Mosercs ..210/413 Sslgnee l'Industries Inc L 3,079,612 3/1963 Corliss ..4/10

geles, Calif.

[22] Filed: Nov. 13, 1970 Primary Examiner-John Adee 1 pp No 89 385Att0mey-Leonard Golove et al.

Related U.S. Application Data Division of Ser. No. 829,486, June 2,1969, Pat. No. 3,567,032, which is a continuation-in-part of Ser. No.737,232, June 14, 1968, abandoned.

[57] ABSTRACT In a recirculating sanitary system, an improved filter andpump assembly provides a source of flushing liquid. A diaphragm pump isprovided with a coupling to a plurality of needle members thatreciprocate through an apertured plate. The needle members ex 52 U.S.c1. ..4/10,210/152,210/413, beymld the Plate the Storage tank at 210/416times, and the reciprocating motion imparted to the 51 1m.cl. ..B0ld29/38 -,1? member; fi clganflthe ES I corn mation, w ic acts ast e iter.e um aso [58] Field of Search ..210/152,355,407,413,414, supplies alimit-ed back flow through thepfiltgr for 210/415, 416; 4/1, 78, 89cleaning purposes during a portion of the operating cycle.

22 Claims, 7\Drawing Figures Toilet Flush line Storage f0 TGl'lk 4 Jl'liSource PATENTEDJAN 9 I975 3.708.806

SHEET 1 OF 3 I2 Fig. l.

Toilet Flush line 20 Storage Tank l4 Pump Filter Source 34 36 Fig. 2.

Fig. 5.

James M. Kem per,

INVENTOR.

PATENTEDJAH 9 I973 3,708,806

sum 3 BF 3 James M Kemper,

INVENTOR.

FILTER AND PUMP FOR A RECIRCULATING SANITARY SYSTEM The presentinvention relates to recirculating sanitary systems, and, moreparticularly, to a system including a toilet, a storage tank, andpumping and filtering means for providing a supply of flushing liquid tothe toilet, and is a divisional application of application Ser. No.829,486, filed June 2, 1969 now U.S. Pat. No. 3,567,032, which was acontinuation-in-part of the application filed June 14, 1968, Ser. No.737,232 now abandoned.

Circulating sanitary systems in which the present invention is usefulhave been described and shown in the U.S. Pats. to W. F. Katona et al.,No. 3,256,221 and J. W. Dietz et al., No. 3,067,433. Pneumaticallyoperated recirculating systems have been disclosed, for example, in therecent U.S. Pats. to C. A. Garver, No. 3,024,933, and W. D. Hicks, No.3,001,205.

In the recirculating sanitary systems, exemplified by the patent toKatona et al., or Dietz, above, utilize an electrically-driven rotarypump in combination with a rotating filter cup. A wiper assembly isprovided to clean the filter during operation to remove solid orparticulate residue from the filter itself. The pump is capable ofreversible operation to allow limited back flushing through the filterfor cleaning purposes. Since, in sanitary systems, fibrous materialssuch as paper or fabric, and yet other foreign objects may becomeentangled with the filter cup and cleaning scrapers or combs, therelative rotation as between the cup and the scraper or comb duringoperation, may cause the fibrous materials or other foreign objects tobe wound around the filter or merely jammed in the assembly. ln eitherevent, rotation is prevented, locking the filter and causing either astalling and burnout of the electrical motor or a failure within thepower train.

It is also noted that with impeller type pumps, the intake of flushingliquid is contemporaneous with the flushing operation, resulting in arequirement that a high volume of liquid be passed through the filterbasket at a time when the storage tank contents are in agitation.Consequently, the high volume flow may be impaired by the circulation ofthe waste and solid matter being drawn toward the filter and pump.

What is needed, and what has been provided by the present invention, isan improved, recirculating system with a novel filter element, that isnot subject to the problems of the prior art.

According to a preferred embodiment of the invention, a large diaphragmpump is provided with a reciprocating arm connected to the diaphragmthereof. In the preferred embodiment, a pneumatic system drives thediaphragm and a bias spring returns the diaphragm to a set initialposition.

The intake to the diaphragm pump includes an apertured plate member anda plurality of needle members connected to the reciprocating arm. Theneedle members reciprocate through the aperture on each actuation of thediaphragm. On the pump stroke of the diaphragm, the needle members movethrough the apertures into the storage tank portion and, on the returnstroke, the needles are withdrawn into the filter assembly.

The clearance provided between each aperture and the correspondingneedle member creates the filtering structure. In the preferredembodiment, the needle members at all times extend through the platemember and into the storage tank, to prevent an occluding of theapertures by impermeable foreign objects.

The diaphragm pump is provided with a first unidirectional flow valve,which is connected to the toilet flushing supply line, and a second,uni-directional flow valve which admits fluid from the storage tank. Thereciprocating arm is loosely mounted in the pump housing so that on thepumping stroke, some fluid is permitted to flow through the filterassembly and into the storage tank, thereby back flushing the filter andclearning particulate residue from the vicinity of the filter apertures.

In the preferred embodiment, the pneumatic system drives the diaphragmpump and a novel, pneumatic time delay apparatus is provided to permit acomplete cycle of operation to be triggered by the momentary actuationof a push button or other start mechanism. The pneumatic system is, atall times, isolated from the recirculating liquid system, and operateswholly independently therefrom. Because the pump stores the liquid to beused in the flush portion of the cycle, high volume flow through thefilter is not required. Rather, the filter operates during a fillportion of a cycle and the rate of fill can be selectively adjusted soas not to disturb the sedimentary contents of the storage tank.Depending upon the demand cycle of the sanitary system, the fill portionof the cycle can be extended so that even a relatively fine filter canbe utilized in the system.

In alternative embodiments, the placement of the return spring can bechanged and the diaphragm pump can be operated utilizing a vacuum linerather than a pressure line. In yet other embodiments, a hydraulicsystem could be utilized, since the driving system is maintainedisolated from the driven system.

Still other pumping mechanisms can be adapted for use in the presentinvention, including electrically driven systems which can provide areciprocating motion to the filtering combination.

For systems wherein a ready supply of pneumatic fluid is not available,it has been deemed desirable to provide a system which incorporates thediaphragm pump and filter assembly of the copending application and theelectrically operated pump of Katona, et al., supra.

In yet another alternative, of the present invention, a diaphragm pumpacts as a partial reservoir of filtered flushing liquid. A conventionalimpeller pump drives filtered liquid through the system and a by-passdrives the pump diaphragm. The impeller pump draws additional liquidthrough the filter as needed and a portion of this liquid is returned,through a by-pass to drive the diaphragm, reciprocating the filterneedles with respect to the plate- Because the pump stores some of theliquid to be used in the flush portion of the cycle, high volume flowthrough the filter is not required. Rather, the filter operates bothduring the flush and fill portions of a cycle. Further, the diaphragmpump, at the end of a flush stroke, refills itself, primarily throughthe filter.

The fluid that is expelled from the driving chamber of the diaphragmpump is returned, through the by-pass and will, during the intake stroketend to stand in the discharge line. At the conclusion of the intakestroke, the standing fluid will provide a limited back flow through thefilter and into the tank, tending to clean the filter plate.

The reciprocating filter assembly may, in alternative embodiments,utilize a reciprocating apertured plate in combination with stationaryneedle members. Further, the fineness of the filter can readily bemodified by the appropriate choice of aperture size relative to thecross-section of .the individual needle members.

The novel features which are believed to be characteristic of theinvention, both as to organization and method of operation, togetherwith further objects and advantages thereof will be better understoodfrom the following description considered in connection with theaccompanying drawings in which several preferred embodiments of theinvention are illustrated by way of example. It is to be expresslyunderstood, however, that the drawings are for the purpose ofillustration and description only and are not intended as a definitionof the limits of the invention.

FIG. 1 is an overall block diagram of a recirculating sanitary system inwhich the present invention is useful;

FIG. 2 is a side view of an integral pump and filter unit according tothe present invention;

FIG. 3 is a side sectional view ofa preferred embodiment of a pump andfilter adapted to be mounted below the storage tank of a sanitarysystem;

FIG. 4 is a top view of the filter portion of the unit of FIG. 3;

FIG. 5 is a magnified side sectional view of the filter portion of theapparatus of FIG. 3;

FIG. 6 is a side sectional view of an alternative filter arrangement inwhich an apertured plate reciprocates and needle members are heldstationary; and

FIG. 7 is a side sectional view of the alternative embodiment of animpeller and diaphragm pump and filter combination adapted to be mountedeither within or below the storage tank ofa sanitary system.

Turning first to FIG. 1, there is shown, in generalized diagrammaticform, the recirculating sanitary system according to the presentinvention in which general blocks have been utilized to represent eachof the elements of such a system. Basic to the system 10 is a toiletelement 12 which is mounted in conjunction with storage tank 14. A flushline 16 supplies flushing liquid to the toilet l2 and the flush liquidand waste matter exits from the toilet 12, directly into the storagetank 14.

A pump and filter combination 18 is connected to the storage tank 14 andis also connected to a source of power through an appropriateconnection. The power may be electrical, hydraulic, or pneumatic, or,may be solely mechanical, depending upon the intended location and useof the system 10.

An appropriate trigger and timing mechanism 20 controls the applicationof power to the pump and filter combination 18 for a predeterminedperiod of time. The period depends upon the intended use of the systemand the volume of flushing fluid required for normal operation of thetoilet 12 relative to the storage capability of the storage tank 14.

In operation, actuation of the trigger assembly 20 permits theapplication of power to the pump and filter combination 18 for thepredetermined period of time.

The pump and filter combination 18 draws and filters fluid from thestorage tank 14 and pumps this fluid through the flush line 16 into thetoilet 12. The fluid is then returned to the storage tank 14 forsubsequent recirculation. Typically, recirculating sanitary systems 10are utilized in mobile vehicles such as aircraft, trailers and mobilehomes, busses, campers and boats.

Turning next to FIG. 2, there is shown a novel pump and filter assembly30 according to the present invention, shown partially submerged in astorage tank 32. The storage tank 32 contains both liquid and solidmatter, such as is generally found in a waste disposal system. As shown,the pump and filter assembly 30 is vention which is adapted to. bemounted below astorage tank. As shown, a pair of rectangular members arejoined at a perimeter flange 40. A first rectangular member 42, which ison the driving" side of the pump, is provided with a fitting 44 to whichis connected a flexible hose 46, that leads to the source of pneumaticfluid (air) under pressure.

An internal diaphragm 48 isolates a driving chamber 50 from a drivenchamber 52 and may be made of a metal or other impervious material. Thediaphragm 48 is mounted in the flange 40,- either by extending thediaphragm 48 into the flange 40 and capturing it therebetween, or, aflexing strip 49 of a more flexible material having a much higherresistance to fatigue and stress is bonded to the diaphragm 48 and isheld by the flange 40. A second rectangular member 54 completes the pumpportion and forms the driven chamber 52 of the pump.

In the embodiment of FIG. 3, the pump is driven by compressed air and,accordingly, a return spring 56 is provided to bias the diaphragm 48into a first or rest position, representing the quiescent .portion ofthe pumping cycle. A reciprocating rod member 58 is concentricallymounted with respect to the return spring 56 and has a disc-shapedfitting 60 at one end, which is fastened to the diaphragm 48. Thediaphragm is provided with a cup-shaped indentation 64 to receive thereturn spring 56. At the opposite end of the spring 56, a correspondingcup-shaped indentation 66 is provided in the second member 54 throughwhich the reciprocating rod member 58 extends and which retains thereturn spring 56 in position.

An outlet fitting 68 is provided through'which filtered liquid can beprovided, through a flexible line 70, to the flush inlet of the toilet.A unidirectional flow valve 72 permits the flush line to have filteredfluid standing therein at all times. The cup-shaped indentation 66provides, external to the pump a filter cylinder which is connected to afilter plate 76. A plurality of circular apertures 78 are formed in thefilter plate 76, into which are fitted a corresponding plurality ofneedle members 80.

The needle members 80 have a cross sectional area that is only slightlyless than the area of the corresponding aperture 78, an annular flowspace 82 is provided of limited area. The plurality of needle members 80and apertures 78 function as a filter since, in general, the annularspace 82 provided is sufficiently small to exclude most particulatematter that may be found in the storage tank and yet enable an adequateflow of filtered liquid to the pump 30.

The plurality of needle members 80 are fixedly mounted on areciprocating plate 84 which is attached to the reciprocating rod member58. The reciprocating rod member 58 extends through the aperture 86 ofthe cup-shaped indentation 66 and some clearance is provided, as betweenthe rod member 58 and the aperture 86. A second, unidirectional flowvalve 88 is positioned to permit a flow of filtered liquid into thedriven chamber 52 from the inner volume of the cup 66.

In operation, air under pressure is connected to the pneumatic line 46,is applied to the driving chamber 50, forcing the diaphragm 48 upward,as viewed in FIG. 3. Motion of the diaphragm 48, assuming no fluidwithin the driven chamber 52, compresses the return spring 56 and movesthe reciprocating arm 58 and the attached needle members 80 upward andthrough the apertures 78 of the filter plate 76, into the volume of thestorage tank.

The diaphragm 48 is driven upward until a final position is reached, asindicated in FIG. 3, determined by the height of the cup-shapedindentations 64, 66. After the predetermined period of time, theconnection to the pressurized source is broken and the line 46 is thenvented to atmosphere, permitting a reduction of the pressure in thedriving chamber 50.

The diaphragm 48 then moves downward, under the force of the returnspring 56. The increase in volume resulting thereby produces a pressuredifferential between the fluid in the storage tank and the drivenchamber 52. Liquid then flows through the annular filtering spaces 82between the needle members 80 and the filter apertures 78 and throughthe unidirectional valve 88 into the driven chamber 52.

At the same time, the reciprocating arm 58 moves downward, pulling theneedle members 80 through the filter apertures 78, thereby removing anymatter which might be adhering to the needle members 80. At thecompletion of the return stroke, the diaphragm 48 is at the restposition again shown in dashed lines and the driven chamber 52 is nowfilled with filtered liquid. Since the return or fill stroke isdifferent from the pump or flush stroke, the flow rate of fluid throughthe filter is not critical.

On the next operation of the pump, the compressed air is again appliedto the driving chamber 50 and the diaphragm 48 is driven upward at anydesired velocity. The filtered fluid then in the chamber 52 flowsthrough the unidirectional valve 72 into the outlet fitting 68 and intothe flush ring of a toilet and the stored volume of fluid flushes thetoilet.

At the same time, a limited amount of fluid flows through the aperture86 surrounding the reciprocating member 58, and this limited flow offluid is forced through the apertures 78 of the filter plate 76 therebyclearing the apertures 78 while the needle members 80 are moving upward.It will be seen that any matter I soon as the pumping, or flush strokeis completed, the

return, or fill stroke is instituted and the pump is refilled with fluidfor the next operation. Since the rate of fill need not be as great asthe rate of flow during the flush cycle, the filter need not draw-solidstoward the filter plate. An appropriate bleed vent to atmosphere in theoperating mechanism selectively determines the time required for thefilling stroke, so that the complete cycle time from flush to flush canbe kept as brief or as long as is desirable.

The reciprocating action of the filter needle members with respect tothe filter aperture 78 keeps the filtering area clear, and the back flowof fluid during the pumping stroke helps to remove potentially cloggingmaterial from the vicinity of the filter opening. Also, the extent towhich the needle members 80 project into the storage tank volume afterthe completion of the return stroke, determines the extent to whichpotentially clogging material of a relatively impermeable nature can bekept from the vicinity of the filtering openings.

Turning next to FIG. 4, there is shown a front view of the filter plate76, the filter apertures 78, and the corresponding needle members 80.The size of the filtering annulus 82 formed by concentrically fitting aneedle member 80 into a filter aperture 78 can be varied and isdetermined only by the number of annuli provided and the size of thesmallest particle which may be passed by the filter without objection.If the fill time is extended, the filter can be relatively fine since aslower rate of flow will not adversely affect the flush portion of thecycle.

FIG. 5 shows, in somewhat greater detail, the arrangement of the filterplate 76, the apertures 78, the needle members 80 fitting therein andthe annuli 82. Also, shown in dashed lines is the position of the needlemembers 80 relative to the filter plate 76 during a pumping stroke ofthe diaphragm 48. With reference to FIG. 5, it can be seen that othervariations are possible in which the needle members 80 might be providedwith a cleaning collar or other appropriate fitting, so that at the endof a pumping stroke, the filter apertures 78 could be substantiallyoccupied by the needle member 80, forcibly driving out foreignparticulate matter. The plate carrying the needle members has beendisclosed and separately claimed in a later application of the inventor,Ser. No. 65,095, filed Aug. 19, 1970.

Turning next to FIG. 6, there is shown a possible alternative embodimentin which a reciprocating arm 58' drives a reciprocating filter plate 176that contains filter apertures 178. A corresponding plurality of filterneedle members 180 is fixedly mounted with respect to the filterassembly. In all other respects the operation of the pump and filterassembly is substantially the same as the embodiments illustrated inFIGS. 3, 4 and 5.

The difference in operation is that the coupling of the reciprocatingarm 58' to the filter plate 176 is by means of a suitable linkage 190 towhich is connected appropriate driving arms 192. A filter cylinder 174is provided with a flexible, collapsible portion 175, so that the volumeinside the filter cylinder can be changed during the reciprocation ofthe filter plate 176.

On a pump stroke, with the arm member 58' moving to the right, thefilter plate 176 is moved to the left and the filter cylinder 174 iscollapsed upon itself partially reducing the volume therein andresulting in an enhanced flow of fluid to the right, thereby clearingthe apertures 178 and the filter plate 176. During the intake stroke,the reciprocating rod 58' moves to the left and the reciprocating filterplate 176 moves to the right. On the pump stroke, the limited flow offluid from the pump into the filter cylinder 174 has an enhanced effecton cleaning the apertured plate in that the collapsing of the filtercylinder 174 also results in a flow of fluidto the right.

It will be understood by those skilled in the art that particular pumparrangement illustrated herein is merely exemplary and that the presentstructure could easily be modified for use with a vacuum system byplacing a return spring in the driving space of the pump. Othermodifications will be evident to those skilled in the art.

In the alternative embodiment of FIG. 8, a pump assembly 30" includes adiaphragm pump 230 which is partially driven by fluid from the flushline, and partly by the action of an impeller pump assembly 232, whichis the primary pumping element of the system. A return spring 256 isprovided to bias a diaphragm 248 into a first or rest position,representing a relatively quiescent portion of the pumping cycle.

The impeller pump assembly 232 includes an electric motor 258 which maybe substantially identical in placement and operation to the electricmotor shown in the above-described patent to Katona et al., and isconnected to a drive shaft, 260 which operates a rotating impellermember 262 in an appropriate pump cavity 264. Operation of the electrocmotor 258 causes the impeller 262 to rotate, drawing fluid from thedriven chamber 252 into a pump outlet fitting 268 which applies drivenfluid through a flexible line 270. Fluid is also applied to the outlet272.

As shown, the upper surface of the second rectangular member 254 isfitted with a plurality of filter apertures 278 and a correspondingplurality of needle member 280 are fitted therein. The needle members278-are mounted on a plate member 284 which is held against thediaphragm 248 by the return spring 265, one end of which rests in agroove 276 provided for that purpose in the plate member 284.

In operation, the diaphragm 248 is normally biased into the drivingchamber 250 and the return spring 256 is fully extended. Depending uponthe level of fluidin a tank 32, filtered liquid will stand in theflushing system at that height and, generally, will be above the outlet268 of the impeller pump 232. When the electric motor 258 is energized,the drive shaft 260 rotates to drive the impeller 262, which forcesfiltered fluid up through the outlet 268 and into the first and secondflexible connections 270, 246.

The action of the impeller 262 reduces the fluid pressure in the drivenchamber 252 and the diaphragm 248 begins to move upwards. Further, theneedle members 280 are set in motion through the apertures 278. Part ofthe output of the impeller 262 is fed back through the outlet 272 intothe flexible line 246, which tends to drive the diaphragm 248 towardsthe upper surface of the driven chamber 252.

The volume of fluid flow into the flexible lines 270, 246 exceeds thefluid storage capability of the driven chamber 252. Accordingly, whilethe needle members 280 are moving outward through the apertures 278, thereduced fluid pressure within the driven chamber 252 causes an inflow ofliquid from the tank 32, through the filter in a direction opposite tothe motion of the needle members 280.

When sufficient liquid has been pumped into the driving chamber 250, thediaphragm 248 advances to its limit of travel which is determined,either by the compressed height of the return spring 256, or by theupturned portion of the diaphragm edges. A timing device (not shown) onthe motor 258 continues to operate the impeller pump 232 until apredetermined quantity of liquid has circulated through the flush line,at which time the power to the motor 258 is interrupted. During thisoperating interval, any fluid requirements of the impeller pump 232 arefurnished through the needle-aperture filter combination.

When the impeller pump 232 stops, the weight of the liquid standing inthe discharge line 270, and the force of the return spring 256 combined,fill the driven chamber 252 and the diaphragm 248 is forced downward,reversing the travel of the needles 280 through the apertures 278,thereby cleaning the needles 280. If the fluid standing in the dischargeline is insufficient to fill the chamber 252, additional fluid will thenbe drawn in through the filter so long as a pressure differential existsas between the driven chamber 252 and the fluid standing in the tank32'.

In addition, fluid is expelled from the driving chamber 250, backthrough the first flexible line 270 and into the impeller pump outlet268. Generally, the volume of the fluid in the discharge line 270 plusthe volume of fluid stored in the driving chamber 250, will exceed thevolume of the driven chamber 252, even with the diaphragm 248 in itsextreme rearward posi tion. Under those circumstances, a back flow willtake place, from the driven chamber 252, through the filter and into thetank 32, thereby cleaning the area in the vicinity of the filterapertures 278 and needles 280.

Thus, there have been shown and described novel pump-filter combinationsespecially useful in recirculating sanitary systems. Variations andmodifications will occur to those skilled in the art and, accordingly,the scope of the invention should be limited only by the claims appendedbelow:

What is claimed as new is:

1. In a recirculating sanitary system, filter means in the liquidrecirculation path comprising in combination:

a.- a barrier member, interposed in the recirculation path, having anaperture for permitting liquid flow therethrough;

extending therethrough, said needle member and said barrier member beingadapted for relative motion in the axial direction of said aperture andneedle member; and

c. transmission means connected to the sanitary system for impartingrelative reciprocating motion as between said needle member and saidbarrier member, said needle member remaining within said barrier memberaperture at the extreme limits of movement,

whereby the spacing between said needle member and said aperture definesthe particle size to be passed by the filter means, and, wherebyreciprocating motion imparted as between said needle member and saidbarrier member, tends to clean said needle member and clear saidaperture.

2. The apparatus of claim 1, including reverse flow means in therecirculation path for causing liquid flow in the directions ofreciprocating motion, whereby matter tending to clog said apertureduring fluid flow in a first direction, is propelled away from saidaperture by fluid flow in a second, opposite direction.

3. The combination of claim 1, wherein said barrier member has aplurality of apertures and further including, positioned in saidapertures, a corresponding plurality of needle members, saidtransmission means imparting relative reciprocating motion as betweensaid barrier member and said plurality of needle members.

4. Apparatus as in claim 1, wherein said barrier member aperture iscircular and said needle member is substantially cylindrical andconcentrically positioned within said aperture.

5. Apparatus of claim 1, wherein said transmission means imparts motionto said needle member. I

6. Apparatus of claim 1, wherein said transmission means includes meansfor reciprocating said barrier member.

7. Apparatus of claim 3, wherein said transmission means are coupled toreciprocate said plurality of needle members.

8. In a recirculating sanitary system including a storage tank and atoilet, means connected between the storage tank and the toilet forsupplying filtered, flushing liquid to the toilet, comprising:

a. pumping means coupled between the tank and the toilet and adapted tostore a predetermined quantity of filtered liquid;

b. means operating said pumping means including a reciprocating memberwhose motion is correlated with the operation of the pumping means;

c. filtering means connected between said pumping means and the storagetank for supplying filtered liquid from the tank to said pumping means,said filtering means including a plate member having an aperture,sealingly interposed between the storage tank and said pumping means,and a needle member fitted within said aperture, to define a fluidpassage of predetermined size, said plate member and said needle memberbeing adapted for relative motion therebetween with respect to saidaperture axis;

d. coupling means connecting said reciprocating member to a one of saidplate member and needle member for imparting reciprocal motion thereto;and

e. filter cleaning means, including a restricted fluid flow passagebetween said pumping means and said plate member, for enabling a limitedflow of liquid into the storage tank during the pumping of liquid intothe toilet;

whereby said needle member in said aperture prevents passage ofparticulate matter, the reciprocating motion imparted as between saidplate member and said needle member continuously cleans said apertureand needle member, and the limited flow of liquid into the storage tankremoves, from the vicinity of said plate member, any potentiallyoccluding residue.

9. Apparatus as in claim 8, above, wherein said reciprocating membermoves in the same direction as fluid flow between the storage tank andsaid pumping means and fluid flow is in a direction generally similar tothe motion of said needle member relative to said plate member, wherebysaid limited fluid flow is accompanied by relative motion of said needlemember in the same direction, cooperating to clear residual matter fromthe vicinity of said plate member.

10. Apparatus as in claim 8, wherein said needle member extends throughsaid aperture into the storage tank at all times, to act as a barrier tomatter tending to occlude said aperture.

11. Apparatus as in claim 8, wherein said plate member includes aplurality of apertures and said filtering means further include acorresponding plurality of needle members, respectively interfittingsaid plurality of apertures, each needle member and aperture defining afluid passage of predetermined size, and wherein said coupling memberimparts relative reciprocating motion as between said plurality ofapertures and said corresponding plurality of needle members.

12. ln a recirculating system, including a pneumatic energy source, thecombination comprising:

a. a pneumatically driven, diaphragm pump having a diaphragm separatingthe pump into a driving portion and a driven portion having an intakeand an outlet;

b. reciprocating means coupled to said diaphragm for transmitting motionthereof;

0. filtering means interposed between said pump intake and a source ofliquid to be pumped, said filtering means including an apertured plate,a needle member positioned within each of the apertures of saidapertured plate, and means coupling said needle members to saidreciprocating means for moving said needle members axially within theapertures.

13. Apparatus as in claim 12, above, said combination further includingtriggerable, pump operating means comprising:

a. a pneumatic valve body interposed between said pump and a pneumaticsupply source, said body having an outlet to atmosphere, and a feedbackcontrol chamber coupled to said pump;

b. a movable control element in said valve body for alternativelyconnecting said pump to the pneumatic source and atmosphere in first andsecond positions, respectively, said control element normally being insaid second position;

c. a push member in said valve body in cooperative relationship withsaid control element for moving said control element from said second tosaid first position;

d. magnetic holding means in said control chamber including a firstmember connected to said body and a second member connected to saidcontrol element, a one of said first and second members being a magnet,said control element in said first position bringing said first andsecond members into a magnetically attracting relationship; and

e, pneumatically driven means in said control chamber connected to saidcontrol element for moving said control element from said first positionto said second position, whereby operation of said push member movessaid control element into said first position operatively intercouplingsaid magnetic holding means to maintain said control element in saidfirst position until pneumatic feedback into said control chamberoperates said pneumatically driven means to overcome the attractiveforce of said magnetic holding means for driving said control elementinto said second position.

14. Apparatus as in claim 13, above, further including a controllablerestriction interposed between atmosphere and said valve body outlet,for regulating the rate at which pneumatic pressure built up in saidpump discharges to atmosphere.

15. Apparatus as in claim 13, above, further including a controllablerestriction between said pump and said feedback control chamber forregulating the rate at which pneumatic pressure applied to said pump isapplied to said control chamber for actuating said pneumatically drivenmeans.

16. Apparatus as in claim 13, above, wherein said pneumatically drivenmeans include a piston connected to said control element and movabletherewith, and said second member is connected to said piston.

17. Apparatus as in claim 16, above, wherein said first member of saidmagnetic holding means is a permanent magnet.

18. In a recirculating sanitary system including a storage tank andtoilet:

a. a primary, impeller pump coupled to the toilet for supplying flushingliquid thereto;

b. a secondary, diaphragm pump adapted to store filtered liquid coupledto said primary pump for supplying flushing liquid thereto;

0. hydraulic supply means coupling a portion of said impeller pumpoutput to drive said diaphragm pump; and d. filter intake means coupledto the diaphragm of said diaphragm pump and adapted to reciprocatetherewith, for drawing and filtering liquid from the storage tank in tosaid diaphragm pump for subsequent use by said impeller pump, whereby asubstantial portion of the flushing charge of filtered flushing liquidis provided to said impeller pump by said diaphragm pump. 19. Apparatusof claim 18, wherein said filter intake means include:

a. filter plate means interposed between said secondary pump intake andthe supply of liquid to be filtered and pumped, said filter plate meanshaving at least one aperture communicating with the supply; needle meansincluding at least one nee e member positioned in said aperture torestrict the flow of liquid therethrough;

c. motion transmission means coupling said diaphragm to said filterplate and needle means for imparting relative motion therebetween;

whereby said needle member and said plate aperture are in motionrelative to each other, and whereby all fluid flow into said diaphragmpump intake is through said aperture partially blocked by said needlemember acting in combination as a filter.

20. Apparatus as in claim 19, above, further including means forpermitting a back flow of liquid through said filter plate intake duringthe pumping portion of an operating cycle, whereby fluid is forcedthrough said filter plate and into the supply during relative motion,tending to clear the area of foreign matter in the vicinity of thefilter plate means.

21. Apparatus of claim 19, wherein said needle member is coupled to saiddiaphragm and whereby said needle member reciprocates relative to saidfilter plate means, for cleaning said needle member and said aperture.

22. Apparatus as in claim 19, wherein said filter plate means include aplurality of apertures and said needle means further include acorresponding plurality of needle members, respectively interfittingsaid plurality of apertures, each needle member and aperture defining afluid passage of predetermined size, and wherein said coupling pluralityof apertures and said corresponding plurality of needle members.

1. In a recirculating sanitary system, filter means in the liquidrecirculation path comprising in combination: a. a barrier member,interposed in the recirculation path, having an aperture for permittingliquid flow therethrough; b. a needle member, positioned in saidaperture and extending therethrough, said needle member and said barriermember being adapted for relative motion in the axial direction of saidaperture and needle member; and c. transmission means connected to thesanitary system for imparting relative reciprocating motion as betweensaid needle member and said barrier member, said needle member remainingwithin said barrier member aperture at the extreme limits of movement,whereby the spacing between said needle member and said aperture definesthe particle size to be passed by the filter means, and, wherebyreciprocating motion imparted as between said needle member and saidbarrier member, tends to clean said needle member and clear saidaperture.
 2. The apparatus of claim 1, including reverse flow means inthe recirculation path for causing liquid flow in the directions ofreciprocating motion, whereby matter tending to clog said apertureduring fluid flow in a first direction, is propelled away from saidaperture by fluid flow in a second, opposite direction.
 3. Thecombination of claim 1, wherein said barrier member has a plurality ofapertures and further including, positioned in said apertures, acorresponding plurality of needle members, said transmission meansimparting relative reciprocating motion as between said barrier memberand said plurality of needle members.
 4. Apparatus as in claim 1,wherein said barrier member aperture is circular and said needle memberis substantially cylindrical and concentrically positioned within saidaperture.
 5. Apparatus of claim 1, wherein said transmission meansimparts motion to said needle member.
 6. Apparatus of claim 1, whereinsaid transmission means includes means for reciprocating said barriermember.
 7. Apparatus of claim 3, wherein said transmission means arecoupled to reciprocate said plurality of needle members.
 8. In arecirculating sanitary system including a storage tank and a toilet,means connected between the storage tank and the toilet for supplyingfiltered, flushing liquid to the toilet, comprising: a. pumping meanscoupled between the tank and the toilet and adapted to store apredetermined quantity of filtered liquid; b. means operating saidpumping means including a reciprocating member whose motion iscorrelated with the operation of the pumping means; c. filtering meansconnected between said pumping means and the storage tank for supplyingfiltered liquid from the tank to said pumping means, said filteringmeans including a plate member having an aperture, sealingly interposedbetween the storage tank and said pumping means, and a needle memberfitted within said aperture, to define a fluid passage of predeterminedsize, said plate member and said needle member being adapted forrelative motion therebetween with respect to said aperture axis; d.coupling means connecting said reciprocating member to a one of saidplate member and needle member for imparting reciprocal motion thereto;and e. filter cleaning means, including a restricted fluid flow passagebetween said pumping means and said plate member, for enabling a limitedflow of liquid into the storage tank during the pumping of liquid intothe toilet; whereby said needle member in said aperture prevents passageof particulate matter, the reciprocating motion imparted as between saidplate member and said needle member continuously cleans said apertureand needle member, and the limited flow of liquid into the storage tankremoves, from the vicinity of said plate member, any potentiallyoccluding residue.
 9. Apparatus as in claim 8, above, wherein saidreciprocating member moves in the same direction as fluid flow betweenthe storage tank and said pumping means and fluid flow is in a directiongenerally similar to the motion of said needle member relative to saidplate member, whereby said limited fluid flow is accompanied by relativemotion of said needle member in the same direction, cooperating to clearresidual matter from the vicinity of said plate member.
 10. Apparatus asin claim 8, wherein said needle member extends through said apertureinto the storage tank at all times, to act as a barrier to Mattertending to occlude said aperture.
 11. Apparatus as in claim 8, whereinsaid plate member includes a plurality of apertures and said filteringmeans further include a corresponding plurality of needle members,respectively interfitting said plurality of apertures, each needlemember and aperture defining a fluid passage of predetermined size, andwherein said coupling member imparts relative reciprocating motion asbetween said plurality of apertures and said corresponding plurality ofneedle members.
 12. In a recirculating system, including a pneumaticenergy source, the combination comprising: a. a pneumatically driven,diaphragm pump having a diaphragm separating the pump into a drivingportion and a driven portion having an intake and an outlet; b.reciprocating means coupled to said diaphragm for transmitting motionthereof; c. filtering means interposed between said pump intake and asource of liquid to be pumped, said filtering means including anapertured plate, a needle member positioned within each of the aperturesof said apertured plate, and means coupling said needle members to saidreciprocating means for moving said needle members axially within theapertures.
 13. Apparatus as in claim 12, above, said combination furtherincluding triggerable, pump operating means comprising: a. a pneumaticvalve body interposed between said pump and a pneumatic supply source,said body having an outlet to atmosphere, and a feedback control chambercoupled to said pump; b. a movable control element in said valve bodyfor alternatively connecting said pump to the pneumatic source andatmosphere in first and second positions, respectively, said controlelement normally being in said second position; c. a push member in saidvalve body in cooperative relationship with said control element formoving said control element from said second to said first position; d.magnetic holding means in said control chamber including a first memberconnected to said body and a second member connected to said controlelement, a one of said first and second members being a magnet, saidcontrol element in said first position bringing said first and secondmembers into a magnetically attracting relationship; and e.pneumatically driven means in said control chamber connected to saidcontrol element for moving said control element from said first positionto said second position, whereby operation of said push member movessaid control element into said first position operatively intercouplingsaid magnetic holding means to maintain said control element in saidfirst position until pneumatic feedback into said control chamberoperates said pneumatically driven means to overcome the attractiveforce of said magnetic holding means for driving said control elementinto said second position.
 14. Apparatus as in claim 13, above, furtherincluding a controllable restriction interposed between atmosphere andsaid valve body outlet, for regulating the rate at which pneumaticpressure built up in said pump discharges to atmosphere.
 15. Apparatusas in claim 13, above, further including a controllable restrictionbetween said pump and said feedback control chamber for regulating therate at which pneumatic pressure applied to said pump is applied to saidcontrol chamber for actuating said pneumatically driven means. 16.Apparatus as in claim 13, above, wherein said pneumatically driven meansinclude a piston connected to said control element and movabletherewith, and said second member is connected to said piston. 17.Apparatus as in claim 16, above, wherein said first member of saidmagnetic holding means is a permanent magnet.
 18. In a recirculatingsanitary system including a storage tank and toilet: a. a primary,impeller pump coupled to the toilet for supplying flushing liquidthereto; b. a secondary, diaphragm pump adapted to store filtered liquidcoupled to said primary pump for supplying flushing liquid thereto; c.hydraulic supply means coupling a portion of said impeller pump outputto drive said diaphragm pump; and d. filter intake means coupled to thediaphragm of said diaphragm pump and adapted to reciprocate therewith,for drawing and filtering liquid from the storage tank in to saiddiaphragm pump for subsequent use by said impeller pump, whereby asubstantial portion of the flushing charge of filtered flushing liquidis provided to said impeller pump by said diaphragm pump.
 19. Apparatusof claim 18, wherein said filter intake means include: a. filter platemeans interposed between said secondary pump intake and the supply ofliquid to be filtered and pumped, said filter plate means having atleast one aperture communicating with the supply; b. needle meansincluding at least one needle member positioned in said aperture torestrict the flow of liquid therethrough; c. motion transmission meanscoupling said diaphragm to said filter plate and needle means forimparting relative motion therebetween; whereby said needle member andsaid plate aperture are in motion relative to each other, and wherebyall fluid flow into said diaphragm pump intake is through said aperturepartially blocked by said needle member acting in combination as afilter.
 20. Apparatus as in claim 19, above, further including means forpermitting a back flow of liquid through said filter plate intake duringthe pumping portion of an operating cycle, whereby fluid is forcedthrough said filter plate and into the supply during relative motion,tending to clear the area of foreign matter in the vicinity of thefilter plate means.
 21. Apparatus of claim 19, wherein said needlemember is coupled to said diaphragm and whereby said needle memberreciprocates relative to said filter plate means, for cleaning saidneedle member and said aperture.
 22. Apparatus as in claim 19, whereinsaid filter plate means include a plurality of apertures and said needlemeans further include a corresponding plurality of needle members,respectively interfitting said plurality of apertures, each needlemember and aperture defining a fluid passage of predetermined size, andwherein said coupling plurality of apertures and said correspondingplurality of needle members.